slgwv's photos with the keyword: Candelaria

Candelaria district, Mineral County, Nevada.

Candelaria district, Mineral County, Nevada. This was the site of the mill for the 19th century ore-crushing operations. Only the (stone) foundation remains--presumably concrete was way too expensive at the time, with the transporation costs. All the superstructure--the timbers, the stamp mills, and so on--is also gone, presumably moved on to the next big strike. They were way too valuable to just abandon! Such mills, even into the 20th century, were build on a slope so that the ore could be moved thru the operation by gravity. The inset photo shows a different view.

The ridge dominating the skyline is a reclaimed heap leach. The scale is apparent from the highway!

The Northern Belle pit in the Candelaria District, Mineral County, Nevada. The pit is large enough that I couldn't fit it all in the picture. This was one of the pits that fueled the 20th century heap-leach operations in the district. In a heap leach, low-grade crushed ore is stacked on top an impermeable sheet, usually thick plastic, and a leaching solution is sprinkled on top--often using the same sort of sprinklers that would be used for irrigation. The leaching solution trickles thru the heap, dissolving out the desired metal, and flows out the side on hitting the impermeable sheet. The leachate--the "pregnant solution" in the jargon--is then collected and the metal extracted. The solution contains reagents that dissolve the desired metal(s)--dilute cyanide, in the case of precious metals, because of the extraordinary affinity of the simple cyanide (CN-) ion for gold and silver. The technique allows extraction of metals from very low grade deposits, at the cost, of course, of excavating enormous quantities of rock. And cyanide contamination is a very real concern. The left inset shows a different view of the pit, almost to the bottom. Altho it probably now contains some water after this season's winter storms, the lack of a pit lake shows how dry the area is--even by Nevada standards! The right inset shows a reclaimed heap leach--it's the smooth, almost trapezoidal ridge dominating the skyline. At least the sides have been bulldozed so they're now more shallow than the angle of repose, which lets vegetation (such as there is!) get re-established.

Candelaria district, Mineral County, Nevada.

Mineral County, Nevada. The Candelaria district was discovered in the 1860s, and production of bonanza-grade oxidized silver ore occurred in the latter 19th century. These ruins date from that phase of activity. The district got a new lease on life beginning in the 1970s, with large-scale heap leach operations. The smooth ridge at the right is actually a reclaimed heap leach. These had all shut down by 2000, and at present there is no obvious activity despite the run-up in silver prices. Insets show close ups of some of the better-preserved stone ruins. Looking more or less west.

Probably Belleville.